PREDICTION OF THE MAXIMUM RELATIVE SUNSPOT NUMBER OF SOLAR CYCLE-22

A suggestion has been made that solar cycles can be classified into two groups with the addition of the diagram of maximum relative sunspot numbers versus ascending periods of cycles for last 21 cycles. Using the relation between the time distance of two successive maxima of the sunspot number and the descending period, and the relation between a maximum and its asceding period, a prediction of the maximum smoothed monthly value of the relative sunspot number of solar cycle 22 is obtained which will occur in 1990.8 ± 0.4 A.D. and be 100.A comparison of the extrema of the relative sunspot number with those of the geomagnetic index A for last five cycles shows that the maxima of A, in a rough average, appear three years later than those of the relative sunspot number.